Tuesday, June 29, 2010

The LA Times has a series of photos of the turtle-rescue efforts taking place, the image below is one of those, and is of a Kemp's Ridley turtle emerging from an oil/sargassum patch - who unfortunately evaded the rescuers.

Photo from Los Angeles Times, Carolyn Cole

And continuing our update on San Diego Sea Turtle's relatives in the Gulf of Mexico, as of Sunday, June 27th, here are the numbers concerning turtles affected by the oil spill. Visit NOAA's Office of Response and Restoration for full details.

580

total number of sea turtles verified from April 30 - June 27 within the designated spill area

98 or 17%

of the 580, the number of live turtles actively rescued on-water

430 or 74%

of the 580; the number of turtles stranded dead

45 or 8%

of the 580; the number of turtles stranded alive

4

of those 45, the number that subsequently died

135

turtles currently in rehabilitation

110 or 81%

total number of turtles that are in rehabilitation that were captured (98) and stranded (37) alive with visible external oil

Photo from Los Angeles Times, Carolyn Cole

Also noteworthy, a young sperm whale was found dead, 77 miles south of the spill site on June 15th. Like the most common species of sea turtle being found in the spill site (Kemp's Ridley), the sperm whale is an endangered species, and happens to be the only endangered resident cetacean (whale) found in this northern part of the Gulf. According to NOAA's same website, "There are no records of stranded whales in the Gulf of Mexico for the month of June for the period 2003-2007." Tissue samples taken from the 25-foot deceased sperm whale will be analyzed to try and determine cause of death and possible impact from oil.

Another cetacean impacted are dolphins. As of June 27th, 55 dolphins have been verified in the designated spill area, and all but 2 were already dead or subsequently died (96%).

Wednesday, June 16, 2010

The South Bay Power Plant looms over the south San Diego Bay's wetlands - Photo by author

An early step in the long-coming process of removing the South Bay Power Plant (SBPP) from the south San Diego Bay occurred today when "SDG&E filed for approval from the California Public Utilities Commission (CPUC) to relocate the company's existing South Bay substation in Chula Vista to a site south of the South Bay Power Plant to open up public access to the waterfront".

This is one of many regulatory and proceedural steps needed before the SBPP is shutdown and removed from the edge of our San Diego sea turtle's home. The California Independent System Operator (Cal-ISO) still needs to remove the "must run status" of the plant before it can be completely shut down, and full environmental reviews, development plans and permits are still to follow this action - but it is one step closer to the changes we knew have been coming for a long time.

So all of you out there who enjoy our sea turtles, birds, fish and other wonderful wildlife who share our great natural resource, the San Diego Bay, keep paying attention to this process and make sure your voice is heard.

The Port of San Diego and the City of Chula Vista in particular will be working hard to coordinate plans to convert the land now occupied by the SBPP to something new and different. And through the participation of citizens, scientist, and policy makers - we have the potential to create a well preserved bayfront environment; which also provides learning and earning opportunity for San Diego's residents and visitors.

There is a spectrum of impact that development can have on the environment and the natural resources (including the turtles). Likewise, there is a spectrum of value - both traditional economic value as well as non-tradition inherent, personal, and enjoyment value - which differing types of development can generate. My hope is that a creative development plan can maximize both the economic and inherent value of the South Bay. For example, a rejuvenated area with shops, restaurants, homes and even hotels could be set off of the bay. While open space, parks, natural wetlands, observation decks, kayak launch/rental, and trails allow residents and visitors alike the chance to enjoy the beautiful coastal ecosystems of the South Bay.

The South Bay Power Plant and the site of our makeshift field research

station during sea turtle monitoring days - Photo by author

I can visualize school groups learning about wetlands and birds, while watching the mullet leap from the water as they scan to see those turtles pop up for a breath of air. Bird-watching enthusiasts could stroll along the wetland edges, taking in the many migration and residential species found in the South Bay; while only having a short 5 minute walk before they take a seat and enjoy a cut of coffee at a small cafe. Giant sea turtles, one of the most charismatic creatures in the ocean, will continue to visit and feed in the South Bay. Jobs can be created, amazing educational experiences can be had, a new recreation opportunity will be accessible; all through smart planning for the upcoming development.

Economic value can coincide with environmental conservation. The two are in no way mutually exclusive. This is our wonderful backyard, this is our wonderful opportunity. Let's continue to be involved in the process, make our opinions and desires heard, and support our leaders and representatives making these decisions about the future of the South Bay.

See the full press release article from SDG&E about this early step here.

total number of sea turtles verified from April 30 - June 13 within the designated spill area

48 or 12%

of the 411; the number of turtles actively rescued on-water

3 and 3

of the 48; the number found dead, and the number that later died

363 or 88%

of the 411; the number of turtles that have stranded

330 or 91%

of the 363; the number of turtles stranded dead

33 or 7%

of the 363; the number of turtles stranded alive

4

of those 33, the number that subsequently died

57

total number of captured (42 live, 3 dead, 3 later died) and stranded (5 live, 4 dead) turtles found with visible external oil

67

turtles currently in rehabilitation

Dolphins are another marine megafauna affected by the spill and the impact is also being tracked by NOAA's ORR. As of June 13th, a total of 41 dead dolphins have been found. 39 were found dead, one later died at the beach, and the other was euthanized.

Marine turtles and dolphins share similarities which put them at risk for similar impacts concerning this oil spill:

Use coastal areas and the Gulf to feed

They will likely ingest oil and associated toxins mixed into the water, as well as tarballs

This exposes the marine animals to surface oil entering the body, as well as the potential inhalation of the petroleum fumes

They live in the water all* the time (*the exception of course being nesting females on the beach)

And unless they can actively avoid the spill-impacted area, they have no choice but to remain in the oil-contaminated water. Continued exposure to the oil and all its associated chemicals and compounds will likely cause physiological and biological impacts (i.e. sloughing of exposed skin, leading to parasite and disease risks; limited food in-take; organ dysfunction; hormone imbalance; abnormal development; changes in blood chemistry; difficulty with salt excretion)

Other serious impacts to marine turtles are also shared with coastal wildlife rather than dolphins, and affects the breeding, nesting, and hatching turtles. As outlined in Chapter 4 of the same NOAA guide, potential impacts include:

Interference with breeding behavior and location of breeding/nesting sites

The oil may affect breeding success and put males as well as females at risk if they aggregate closer to shore than they would otherwise while feeding or migrating

The oil may disrupt environmental cues that are thought to guide breeding and nesting turtles to the nesting and breeding sites (i.e. masking olfactory cues)

Reduced food supply

This includes the kill-off and/or contamination of fish and invertebrates, as well as damaged seagrass beds, and reefs, especially as the oil begins to wash ashore and congeals

The eggs/hatchlings are at high risk for decreased survival and increased deformities when exposed to "freshly" spilled oil (i.e. the oil spill occurs during nesting season; as opposed to heavily weathered oil)

Nests could become smothered in oil/tarballs, which would prevent the exchange of air (oxygen and carbon dioxide) as well as inhibiting the proper amount of moisture within the nest

The nest temperature may be increased due to the darker color of the oil-contaminated sand - and because male/female ratio of hatchlings in a nest is determined by nest-temperature; oil on the nest or in the sand would raise the nest temperature, creating more females and fewer males

All of these impacts threaten the long-term turtle population levels

Hatchlings:

Oil on the beach could trap, entangle, contaminate/poision emerging hatchlings

Once in the water, hatchlings are moved by currents, gathering them with other floating objects - which usually includes seaweed and food - but now also includes oil

Hatchlings do not dive the way older turtles do, instead they spend much more time at the surface, exposing them to aggregated oil and the fumes

Hatchlings and juvenile turtles are often thought to be indiscriminate foragers, which means they eat what they find - which now includes oil and tarballs

All of these impacts threaten the long-term turtle population levels

Sea turtles are long-lived creatures, which have navigated the oceans for hundreds of millions of years. The list of threats sea turtles encounter throughout their lives is long; and this horrible human-error is just one more giant black mark we have made on their (and our!) environment.

Feel sad, yes. Feel mad, yes. Help, yes.But most of all - look at the way you live your life.

What choices do you make everyday that are related to this human impact?What could you do differently to make that impact just a little bit smaller?

Monday, June 14, 2010

Our first turtle of the 2009-2010 monitoring season was equipped with a satellite GPS tag on November 5th, 2009. Anyone who was interested in following this turtle, named Bonita, could sign up on SeaTurtle.org to receive updates by email as Bonita continued on her journey. After spending at least a few months (see Nov-Jan tracks) in the San Diego Bay, Bonita's tag was removed and used to follow another sea turtle.

Bonita's tag had been placed on a leatherback sea turtle!

On April 15th I received an email showing that this new turtle wasn't in California's waters anymore! And three subsequent emails, the latest one coming just this morning, shows that the leatherback has traveled over 6,700 miles (10,819 km), crossing the entire Pacific ocean, and is currently north of Papua New Guinea! This tag has been transmitting information for over 200 days. This preliminary information - posted earlier this week - was at first thought to be on a green sea turtle - which didn't really make a whole lot of sense! - because this type of migration is not part of their life cycle. So, it has now been confirmed by researchers in charge of this project - that the tag was placed on a leatherback sea turtle - who now appears to be nesting in Jamursba Medi, in West Papua.

In San Diego, we have green sea turtles in the Bay, but other species of sea turtles found off California's coast travel great distances and even cross the Pacific. Leatherback sea turtles (Dermochelys coriacea) tagged off of California's central coast have been tracked all the way to the South Pacific where they nest in Papua, Indonesia. And some loggerhead turtles (Caretta caretta) feed on pelagic crabs off of Baja, Mexico and nest thousands of miles away in Japan.

NOAA's Facebook page has posted some photos (shown above and below) of the driftlines being searched for turtles as well as a couple of the juvenile turtles that were rescued during the efforts taking place 20-40 miles offshore. (Photo: from NOAA Facebook - courtesy of Georgia Dept. Natural Resources, showing senior biologist searching for turtles within the oilfilled Sargassum driftline. )

Yet according to a June 4 blog post by Dr. Charles Innis of the New England Aquarium who is in Louisiana helping with the efforts, no new turtles were brought into the local rehabilitation center, the Audubon Aquarium of the Americas (AOA) between June 1-4 (and presumably the 5th as well) due to the bad weather in the Gulf. But on Sunday, June 6, at-sea efforts resumed, and five more turtles were captured, all but one were still alive and are now in rehabilitation.

the number of additional turtle's verified within the designated spill area in the last week

300

total number of sea turtles verified from April 30 - June 6 within the designated spill area

248 or 83%

total number of turtles stranded dead

22 or 7%

total number of turtles stranded alive

3

of those 22, the number that subsequently died

30 or 10%

total number of turtles captured during on-water rescue efforts by NOAA, Florida Fish & Wildlife Conservation Commission and other trained partners.

25

of the 30 rescued turtles, the number in rehabilitation at Audubon Aquarium

2:3

the number captured that were already dead; and the number which later died

35

of the stranded (5) and captured turtles (30) with visible external evidence of oil

4:1

the number stranded alive: the number stranded dead

2

number of the 4 stranded alive that were caught during skimming operations

41

turtles in rehabilitation

Many different groups have pitched in to help with the turtle-specific rescue efforts, including veterinarians from the NEA who are putting updates (when they get a break) on their own rescue blog. Check it out to see more photos and hear details about the work being done once rescued turtles are brought to shore at the Audubon Aquarium of the Americas in New Orleans.(Photo: from NOAA's Facebook page - courtesy of NOAA & Georgia DNR, showing NOAA veterinarian cleaning a recently rescued juvenile Kemp's Ridley.)

Once at the AOA, the turtles are examined, cleaned, and treated. In addition to the NEA blog with great photos and first hand accounts of the efforts, The Louisiana Marine Mammal and Sea Turtle Rescue Program (LMMSTRP) is another one of the many partners helping in this effort, and have posted additional photos of the cleaning process on Flickr.

Weather reports of continuing southwesterly winds indicate that the oil slick is expected to continue moving north towards Louisiana as well as the Mississippi and Alabama barrier islands, and east toward the Florida Panhandle.

The next post will focus on another common theme of this San Diego Sea Turtle blog, and that is on the economic value of marine life and the ocean's resources.

Until then, the best sign off again seems to be with a big "Thank You!" to all the people helping with the rescue and cleanup efforts; and positive thoughts for the gushing to stop.

Tuesday, June 1, 2010

The green sea turtles (Chelonia mydas) that are found in San Diego Bay are of part of the Pacific population which is listed as endangered and is therefore protected and closely managed. Similarly, other species and populations of sea turtles found along U.S. coasts and in U.S. waters are protected and closely monitored; all five species of sea turtles found within U.S. waters are listed as either endangered or threatened. All five of these species are found within the Gulf of Mexico.

A sixth species, the Olive ridley (Lepidochelys olivacea) is found along the Pacific coast - usually Mexico and south. The seventh species of sea turtles, the Australian Flatback (Natador depressus), is only found in waters near Australia and Papua New Guinea. (photo by C Turner T, Green turtle near St. Thomas)

total number of sea turtles verified from April 30 to May 31 within the designated spill area

228 or 90%

total number of turtles stranded dead

15

number of turtles stranded alive

3

of those 15, the number that subsequently died

7

number of turtles captured May 31 "alive and very oiled" (6 Kemp's ridleys, 1 green; all pelagic-stage juveniles) by a "directed search efforts from a search vessel that included NOAA, Florida Fish and Wildlife Commission staff and other partners"

40 mi

distance offshore the NOAA+partners team was that captured the above mentioned 7 turtles

12 and 1

of the 253 turtles verified within the spill area, the number of alive (12) and dead (1) turtles collected with "visible external evidence of oil. All others have not had visible evidence of external oil."

21

turtles in rehabilitation

The summary report also states that, "turtle strandings during this time period have been higher in Louisiana, Mississippi and Alabama than in previous years for this same time period. This may be due in part to increased detection and reporting, but this does not fully account for the increase." Even without the oil spill, the turtles in the Gulf of Mexico, like all ocean waters, are subject to many threats which cause mortalities every year. These threats include entanglement (in active and abandoned fishing gear, as well as debris/pollution), fishery bycatch, natural predation (i.e. sharks) and poaching, cold-stun/hypothermia during cold snaps, diseases and parasite-related infections, and habitat loss (includes nesting beaches and foraging grounds such as seagrass beds and coral reefs).

My advisor from NOAA's Southwest Fisheries Science Center has even joined in the efforts to rescue some of these turtles, off the Louisiana coast, from some of the many oil driftlines.Driftlines are usually made up of floating alga - usually Sargassum - and other floating debris that are brought together from currents and wind into these convergence zones. Juvenile turtles, especially, use these floating patches to rest in, feed in, and avoid predators. However, the oil which is being clumped together at the surface is also becoming collected in these driftlines. (photo: loggerhead hatchlings in Sargassum)

Although surprisingly robust when faced with physical damage (shark attacks, boatstrikes), sea turtles are highly sensitive to chemical insults such as oil.

Areas of oil and gas exploration, transportation, and processing often overlap with important sea turtle habitats.

Sea turtles are vulnerable to the effects of oil at all life stages—eggs, post-hatchlings, juveniles, and adults in nearshore waters.

Several aspects of sea turtle biology and behavior place them at particular risk, including a lack of avoidance behavior, indiscriminate feeding in convergence zones, and large predive inhalations.

Oil effects on turtles include increased egg mortality and developmental defects, direct mortality due to oiling in hatchlings, juveniles, and adults; and negative impacts to the skin, blood, digestive and immune systems, and salt glands.

(From page 35)

Clearly this blog is specifically focused on sea turtles, yet the reason I personally am dedicated to studying these long-lived, migratory, charismatic animals is because they are excellent sentinels to the overall ocean health. Through studying the well-being of turtles and their habitats, we also learn a great deal about several ocean ecosystems, marinelife, and even our own coastal safety, homes/businesses and economy.

These are just some initial details and information about the current disaster and its impact on marine turtles... more to come. Until then - here's to keeping our fingers crossed that the spewing stops soon; and here are many thanks to those folks who are out there helping to protect and rescue the marine and coastal resources that are oh-so-important and wonderful.

About Me

Cali is a Postdoctoral Fellow at University of California, San Diego's Ecology program, having received her Ph.D. in Ecology, Behavior
& Evolution. She is a graduate of UCSD's Scripps Institution of Oceanography, where she received her Masters in Marine Biodiversity and Conservation. Her work conducting environmental monitoring in San Diego includes assisting NOAA researchers monitor the population of green sea turtles in the San Diego Bay. The work highlighted on this blog is in partnership with NOAA's Southwest Fisheries Science Center (see links for more information).